The invention generally relates to curable compositions including cyanate ester resins. More particularly, the invention relates to cyanate ester resin compositions for encapsulating components of an electrical machine.
Thermosetting resins are typically used as electrically insulating encapsulating (e.g., potting) materials for electrical machines. Thermosetting resins, such as cyanate ester resins, have desirable mechanical properties, thermal stability, and chemical resistance. However, when used at high temperatures, the performance of some of these materials may be unsatisfactory and may result in significant thermal degradation even after short operating times. The conventional encapsulating materials may further generate cracks and produce excessive heat at the operating temperature of the electrical machines. So, it may be desirable to improve the thermal conductivity as well as the mechanical properties of the cyanate ester resins used for encapsulating materials. Improved materials for dissipating heat generated in electrical machines are also desirable, particularly for generators used in aircraft and other aerospace applications.
Therefore, electrically insulating encapsulating materials that can be used at high temperatures, and are effective in dissipating heat from electrical machines are desirable. Further, improved methods for encapsulating components of an electrical machine are also desired.